<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>性能优化：虚拟列表</title>
</head>

<body>
    <button id="button">button</button>
    <!-- 列表 -->
    <ul id="container"></ul>
    <script>
        document.getElementById("button").addEventListener('click', function () {
            let now = new Date()
            // 插入一万条
            const total = 10000;
            let ul = document.getElementById('container')
            let oFragment = document.createDocumentFragment('oFragment')
            for (let i = 0; i < total; i++) {
                let li = document.createElement('li');
                li.innerText = Math.ceil(Math.random() * total)
                oFragment.appendChild(li);
            }
            ul.appendChild(oFragment)
            console.log('JS运行时间:', Date.now() - now);
            setTimeout(() => {
                console.log('总运行时间:', Date.now() - now);
            }, 0)
        })
    </script>
</body>

</html>